The size numbers of the four perfect intervals, separated by commas.

In the 10th grade, i was teamed up in a group of four. our project was on modern history. altho it seemed super hard for many of us. patrick fleming  took charge and showed us the understanding of this project.  his leadership showed great ethics and it taught me, personally, how to others understand, not just to show them, but explain it thoroughly. and altho he was a great teacher i would have changed a few things. one being his attitude. many times he would get frustrated and impatient with the group.  i think  a leader i would have done exactly  what he did but with much more patience and be there more to explain. such as lunch  learning. and giving everybody a chance to try to explain it in their  head. 

Answerstructural and frictional unemployment;